Some terms and distinctions – related to religiosity

ReligiousA standard definition:
pertaining to, or concerned with, or in accordance with the principles of a religion;In a religious naturalist context:
actively interested in or caring about, considering, and acting upon themes and questions that have been considered by traditional religions, as in forming a worldview (how things are; what things matter; what is right and just and good) and trying to live in accordance with valuesAs described by John Dewey (distinguishing between a religion and the religious):
a felt quality of unity and purpose within the finite experiences that we have

Religion
(derived from the Latin, religare, to fasten or bind)
a personal set or institutionalized system of beliefs concerning the cause, nature, and purpose of the universe, usually involving ritual observances and often containing a moral code; usually includes, but does not require, belief in and reverence for a creative force or creator

Spiritual
pertaining to spirit (as in a life-force or the essential quality in beings or phenomena); use to distinguish interest in sacred matters from a secular orientation; (while “spiritual” and “religious” are similar in many ways, the connotation of “spiritual” is mainly individual, while “religious” suggests connection to the teachings of specific traditions or institutions)

Secular
(from the Latin saeculum, the present world) relating to the worldly or temporal; not overtly religious